1. Field of the Invention
The present invention relates to a plastic packaging made from a packaging cavity and a cover film, wherein the cover film is at least partially sealed in the sealing region to the packaging cavity so as to be peelable and the cover film, or the packaging cavity, comprises at least one knob and the packaging cavity or the cover film complementary to this has at least one recess, through which the knob(s) is(are) pushed upon sealing the plastic packaging, wherein at least one partial region of at least one knob is provided with a sealing material or preferably at least one partial region of at least one knob and the edge region of the complementary recess are connected with a sealing material which is damaged upon first opening of the packaging.
2. Brief Description of Related Developments
The invention further relates to methods for the manufacture of the packagings according to the invention.
Goods for packaging, foodstuffs in particular, are nowadays increasingly offered for sale in plastic packaging. This plastic packaging has a packaging cavity in which the packaged goods are disposed and a cover film. The cover film is sealed to the packaging cavity. As the goods to be packaged are frequently not used immediately after opening, it is advantageous if the packaging can be re-sealed after opening.
There was therefore no lack of trials in the past to make available re-sealable packaging. EP 0 564 695, DE 39 25 746, EP 0 386 490, DE 39 41 183, EP 0 408 516, WO 97/05023, EP 0 716 986, EP 0 595 368, EP 0 579 262, EP 0 506 295, EP 0 427 513, EP 0 427 512, EP 0 385 565, EP 0 381 329 or EP 0 379 927 are cited here only as examples in which either procedures or devices for the manufacture of re-sealable packaging and/or the re-sealable packaging itself are taught.
All re-sealable packagings disclosed in the above-mentioned publications have either the disadvantage that they are expensive to manufacture and/or are not effectively re-sealable.
The German patent application with the file reference DE 198 59 042.3 teaches a plastic packaging provided with knobs comprising a packaging cavity and a cover film, the cover film being sealed to the packaging cavity in the sealing region so as to be at least partially peelable and the cover film or the packaging cavity having at last one knob and the packaging cavity or the cover film having at least one recess complementary to this, through which the knob is pushed, so that the plastic packaging is re-sealable after opening.
The disadvantage with plastic packaging provided with knobs is that the user of the closed packaging mostly cannot discern the extent to which the packaging is still in the unopened original state, or whether the packaging has already been opened. With original, sealed packaging the user generally assumes the product content has not been consumed. Plastic packaging provided with knobs in particular for perishable foodstuffs makes the user uncertain.